Load balancing mechanisms are often incorporated in devices that provide adjustable positioning of one or more types of equipment. Such mechanisms can be useful for adjusting forces within a positioning device that would otherwise vary depending upon, for example, the particular load or the particular position of the load within a range of movement provided by the positioning device. Some articulated positioning devices include load balancing mechanisms particularly in order to assist an operator with manual positioning of different types of equipment.
One example of a positioning device that may incorporate a load balancing mechanism is a device for positioning an electronic display (e.g., monitor, television, etc.) and/or a computer. Many jobs involve working with personal computers and/or display monitors. In such jobs, the personal computers and/or display monitors may be used by multiple operators at different times during a day. In some settings, one computer and/or monitor may be used by multiple people of different sizes and having different preferences in a single day. Given the differences in people's size and differences in their preferences, a monitor or display adjusted at one setting for one individual may be inappropriate for another individual. For instance, a child would have different physical space needs than an adult using the same computer and monitor. Further, a single user may wish to periodically adjust the position of a display and/or other equipment in order to perform operations in various postures.
For equipment requiring frequent manual adjustment, lift assistance has been provided using gas springs, extension springs, and other types of energy providing devices. However, gas springs are costly and wear out over time. In addition, gas springs usually require a significant amount of space, for instance arm length, which can be at a premium in certain applications. In addition, some types of wire springs provide lift assistance that varies depending upon the extent of the spring compression or extension, which can provide uneven assistance through the range of movement and make some movements more difficult for manual operators.
As adjustable height mechanisms for displays have become more widespread and users have experienced their advantages, users are more frequently adjusting the height of their monitors and other equipment. Further, such adjustments are now more frequently desired over a wide range of travel. Moreover, as equipment grows in size and weight, ease of adjustability is an important consideration. While current load balancing mechanisms can address some of these issues, there is a continuing desire to increase weight capacity and/or reduce the size of positioning devices in order to accommodate bigger equipment. In addition, there is a desire for load balancing mechanisms and positioning devices which are compact, less costly to manufacture and maintain, have increased reliability, allow easy adjustability, are scalable to many different sized monitors, are adaptable to provide a long range of travel, and/or are adaptable to provide constant support force as the equipment is being positioned.